This photograph illustrates the technique for performing a median motor nerve conduction study, recording from the abductor pollicis brevis (APB) muscle. The recording electrode (G1, black) is placed over the belly of the APB. The reference electrode (G2, red) is placed at the proximal phalanx of the thumb. The distal stimulation site is at the wrist, proximal to the distal wrist crease. The distance between G1 and the distal stimulating site at the wrist should be about 4-6 cm.